Magnetic disk drives are used to store and retrieve data in many electronic devices including computers, televisions, video recorders, servers, digital recorders, etc. A typical magnetic disk drive includes a head having a slider and a transducer with a read and write element that is in very close proximity to a surface of a rotatable magnetic disk. As the magnetic disk rotates beneath the head, a thin air bearing is formed between the surface of the magnetic disk and an air bearing surface (ABS) of the slider. The read and write elements of the head are alternatively used to read and write data while a suspension assembly positions the head along magnetic tracks on the magnetic disk. The magnetic tracks on the magnetic disks are typically concentric circular regions on the magnetic disks, onto which data can be stored by writing to it and retrieved by reading from it.
The slider is aerodynamically designed to fly above a rotating magnetic disk by virtue of an air bearing created between the ABS of the slider and the rotating magnetic disk. The ABS is the portion of the slider surface which is closest to the rotating magnetic disk, which is typically the head portion of the slider. The slider can also support a laser source that provides energy during writing in processes such as a heat assisted magnetic recording (HAMR) process. HAMR is a process used for recording information on magnetic medium having high coercivity. Magnetic medium having a large magnetic anisotropy constant Ku is sometimes preferred because it is thermally more stable than magnetic medium having a small Ku. Since magnetic medium with high Ku also has high coercivity, in cases where high Ku magnetic media is preferred, the preferred medium also has high coercivity. Recording information onto high Ku magnetic medium can be difficult because of the coercive forces of the magnetic recording medium. HAMR makes it easier to record onto a high Ku magnetic medium by applying heat with the use of a laser diode (LD), which is mounted onto the slider near the head.
HAMR uses a laser source to provide energy during the writing process. The energy source comes from an LD chip that is attached to a power source. The LD is also attached to the back of the slider and the light energy is guided to the ABS surface through a waveguide to heat the medium film for writing.
LD devices are often tested and screened before they are selected for use in a magnetic disk drive. The LD testing and screening processes are performed as part of a burn-in process of the LD. The burn-in process is used to screen out LD devices having “infant mortality” but often do not fail until they are used for some time. Incorporating testing and screening with the burn-in process helps reduce the number of magnetic hard drives that fail in the field as a result of having the LD devices fail. During the burn-in process, the LD is loaded into a fixture and heated at an elevated temperature for several hours with the LD energized.
Fixtures that are currently used to burn-in and test LD devices typically have contact probes as part of the fixture. The functions of the contact probes are to hold the LD devices in place on the fixture and to make electrical contact to the P-side and N-side of the LD. However these fixtures, which are currently used, have drawbacks. The integrated contact probes and moving shims, which are used to “lock” the components, are expensive to fabricate due to their complex design and are expensive to maintain because it is difficult to align and maintain the probes. Existing fixture designs are also limited in the number of LD devices that the fixture can support due to the probe design. Further, existing fixture designs are difficult to work with because it is difficult to load LD devices into the existing fixtures.
Therefore, what is needed is a system and method for LD testing and screening that is less expensive to use and maintain than existing fixtures while at the same time increases the number of devices per fixture, and provides for easy automated loading of the fixture.